First and foremost you must understand that unless your body fat percentage is around ten per cent your abs simply will not be visible. If you're carrying a little additional timber know your time will be better spent doing hill sprints than on the gym floor performing the latest ab routine you found in a fitness magazine.

As a general rule of thumb, the more muscle fibres you recruit to perform a certain exercise, the greater the fat burning potential of that particular exercise. If your goal is to lower your body fat and unveil your rectus abdominis muscles the small, isolated nature of sit-ups won't really compare to powerfully engaging the arms and legs to propel you up a 45-degree climb.

2. You think sit-ups work

Without a doubt, the biggest mistake made by men the world over is this idea that sit-ups actually work. Yes, they're better than nothing but research from the Department of Kinesiology at the Pennsylvania State University shows your efforts would be far better spent learning less well-publicised core exercises.

Researchers have compared sit-ups with planks - an exercise where you get into a press-up position, rest on your elbows and hold for 30 to 90 seconds. Using surface electromyography (EMG) electrodes they discovered there was 20 per cent greater muscle activation in the plank compared to the sit-up. Train smarter, not harder and maybe re-think your ab routine.

3. You're not getting enough rest

This point is particularly important for those people guilty of trying to fit a year's worth of training into one week as they frantically try and find their abs for a beach holiday. It simply won't work. What's worse is those 6.00am morning runs might even be doing your quest for a six-pack more harm than good.

Researchers from the Rambam Medical Centre in Haifa, Israel found that not getting enough sleep could bring about hormonal changes in the body that increase stress, appetite and possibly the amount of fat we hold around our stomach. Press the snooze button - you'll be biochemically better equipped to gain a six-pack if you do.

4. You're not training hard enough

This final reason is for those people who leisurely set the treadmill to level four and expect to stroll their way to a six-pack. The
harsh reality is you have to be prepared to earn your six-pack. Granted, sleep
and recovery are important, but
when it's time to work you've got to do just that.

Scientists from Laval University in Québec, Canada have published research showing that high-intensity training was so much more effective at burning body fat than low-intensity training. As well as increasing metabolism, they also concluded: "the metabolic adaptations taking place in the skeletal muscle in response to high-intensity training appear to favour the fat loss process."